Oral pharmaceutical compositions containing taxanes and methods of treatment employing the same

ABSTRACT

Pharmaceutical compositions for oral administration to mammalian subjects comprise a taxane or taxane derivative (e.g., paclitaxel or docetaxel) as active ingredient and a vehicle comprising at least 30% by weight of a carrier for the taxane, said carrier having an HLB value of at least about 10. The compositions may also comprise 0-70% of a viscosity-reducing co-solubilizer. The compositions may be incorporated into conventional oral pharmaceutical dosage forms, or can be in the form of a two-part medicament wherein the first part includes the taxane in a solubilizing vehicle and the second part comprises a carrier for the taxane to promote oral absorption. Methods of treatment of taxane-responsive disease conditions employing the novel compositions are also disclosed, whereby the compositions can be administered alone or in association with an oral bioavailability enhancing agent.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending application Ser. No.09/055,818, which is a continuation-in-part of co-pending applicationSer. No. 08/863,513, abandoned, which is a continuation-in-part ofapplication Ser. No. 08/733,142, filed Oct. 16, 1996, now U.S. Pat. No.6,245,805, which is a continuation-in-part of application Ser. No.08/608,776, filed Feb. 29, 1996, now U.S. Pat. No. 5,968,972, whichclaims the priority of provisional application Ser. No. 60/007,071,filed Oct. 26, 1995.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to compositions for orally administeringpaclitaxel and related taxanes to human patients, and methods oftreatment employing such compositions.

2. Description of the Prior Art

Many valuable pharmacologically active compounds cannot be effectivelyadministered by the oral route to human patients because of poor orinconsistent systemic absorption from the gastrointestinal tract. Thesepharmaceutical agents are, therefore, generally administered viaintravenous routes, requiring intervention by a physician or otherhealth care professional, entailing considerable discomfort andpotential local trauma to the patient and even requiring administrationin a hospital setting with surgical access in the case of certain IVinfusions.

One of the important classes of cytotoxic agents which are not normallybioavailable when administered orally to humans are the taxanes, whichinclude paclitaxel, its derivatives and analogs. Paclitaxel (currentlymarketed as TAXOL® by Bristol-Myers Squibb Oncology Division) is anatural diterpene product isolated from the Pacific yew tree (Taxusbrevifolia). It is a member of the taxane family of terpenes. It wasfirst isolated in 1971 by Wani et al. (J. Am. Chem. Soc., 93:2325,1971), who characterized its structure by chemical and X-raycrystallographic methods. One mechanism for its activity relates topaclitaxel's capacity to bind tubulin, thereby inhibiting cancer cellgrowth. Schiff et al., Proc. Natl. Acad. Sci. USA, 77:1561-1565 (1980);Schiff et al., Nature, 277:665-667 (1979); Kumar, J. Biol. Chem., 256:10435-10441 (1981).

Paclitaxel has been approved for clinical use in the treatment ofrefractory ovarian cancer in the United States (Markman et al., YaleJournal of Biology and Medicine, 64:583, 1991; McGuire et al., Ann.Intern. Med., 111:273, 1989). It is effective for chemotherapy forseveral types of neoplasms including breast (Holmes et al., J. Nat.Cancer Inst., 83:1797, 1991) and has been approved for treatment ofbreast cancer as well. It is a potential candidate for treatment ofneoplasms in the skin (Einzig et al., Proc. Am. Soc. Clin. Oncol.,20:46), lung cancer and head and neck carcinomas (Forastire et al. Sem.Oncol., 20:56, 1990). The compound also shows potential for thetreatment of polycystic kidney disease (Woo et al, Nature, 368:750,1994) and malaria.

Paclitaxel is only slightly soluble in water and this has createdsignificant problems in developing suitable injectable and infusionformulations useful for anticancer chemotherapy. Some formulations ofpaclitaxel for IV infusion have been developed utilizing CREMOPHOR EL™(polyethoxylated castor oil) as the drug carrier because of paclitaxel'saqueous insolubility. For example, paclitaxel used in clinical testingunder the aegis of the NCI has been formulated in 50% CREMOPHOR EL™ and50% dehydrated alcohol. CREMOPHOR EL™ however, when administeredintravenously, is itself toxic and produces vasodilation, laboredbreathing, lethargy, hypotension and death in dogs. It is also believedto be at least partially responsible for the allergic-type reactionsobserved during paclitaxel administration, although there is someevidence that paclitaxel may itself provoke acute reactions even in theabsence of Cremophor.

In an attempt to increase paclitaxel's solubility and to develop moresafe clinical formulations, studies have been directed to synthesizingpaclitaxel analogs where the 2′ and/or 7-position is derivatized withgroups that would enhance water solubility. These efforts have yieldedprodrug compounds that are more water soluble than the parent compoundand that display the cytotoxic properties upon activation. One importantgroup of such prodrugs includes the 2′-onium salts of paclitaxel anddocetaxel, particularly the 2′-methylpyridinium mesylate (2′-MPM) salts.

Paclitaxel is very poorly absorbed when administered orally (less than1%); see Eiseman et al., Second NCI Workshop on Taxol and Taxus(September 1992); Suffness et al. in Taxol Science and Applications (CRCPress 1995). Eiseman et al. indicate that paclitaxel has abioavailability of 0% upon oral administration, and Suffness et al.report that oral dosing with paclitaxel did not seem possible since noevidence of antitumor activity was found on oral administration up to160 mg/kg/day. For this reason, paclitaxel has not been administeredorally to human patients in the prior art, and certainly not in thecourse of treating paclitaxel-responsive diseases.

Docetaxel (N-debenzoyl-N-tert-butoxycarbonyl-10-deacetyl paclitaxel) hasbecome commercially available as TAXOTERE® (Rhone-Poulenc-Rorer S.A.) inparenteral form for the treatment of breast cancer. To date, noreference has been made in the scientific literature to oral absorptionof docetaxel in animals or patients.

It has been speculated that, in some cases, the poor or non-existentbioavailability of a drug such as paclitaxel after oral administrationis a result of the activity of a multidrug transporter, a membrane-boundP-glycoprotein, which functions as an energy-dependent transport orefflux pump to decrease intracellular accumulation of drug by extrudingxenobiotics from the cell. This P-glycoprotein has been identified innormal tissues of secretory endothelium, such as the biliary lining,brush border of the proximal tubule in the kidney and luminal surface ofthe intestine, and vascular endothelial cells lining the blood brainbarrier, placenta and testis.

It is believed that the P-glycoprotein efflux pump prevents certainpharmaceutical compounds from transversing the mucosal cells of thesmall intestine and, therefore, from being absorbed into the systemiccirculation. A number of known non-cytotoxic pharmacological agents havebeen shown to inhibit P-glycoprotein, including cyclosporin A (alsoknown as cyclosporine), verapamil, tamoxifen, quinidine andphenothiazines, among others. Many of these studies were aimed atachieving greater accumulation of intravenously administered cytotoxicdrugs inside tumor cells. In fact, clinical trials have been conductedto study the effects of cyclosporine on the pharmacokinetics andtoxicities of paclitaxel (Fisher et al., Proc. Am. Soc. Clin. Oncol.,13: 143, 1994); doxorubicin (Bartlett et al., J. Clin. Onc. 12:835-842,1994); and etoposide (Lum et al., J. Clin. Onc. 10:1635-42, 1992), allof which are anti-cancer agents known to be subject to multidrugresistance (MDR). These trials showed that patients receivingintravenous cyclosporine prior to or together with the anti-cancer drugshad higher blood levels of those drugs, presumably through reduced bodyclearance, and exhibited the expected toxicity at substantially lowerdosage levels. These findings tended to indicate that the concomitantadministration of cyclosporine suppressed the MDR action ofP-glycoprotein, enabling larger intracellular accumulations of thetherapeutic agents. For a general discussion of the pharmacologicimplications for the clinical use of P-glycoprotein inhibitors, see Lumet al., Drug Resist. Clin. One. Hemat., 9: 319-336 (1995); Schinkel etal., Eur. J. Cancer, 31A: 1295-1298 (1995).

In the aforedescribed studies relating to the use of cyclosporine toincrease the blood levels of pharmaceutical agents, the activeanti-tumor agents and the cyclosporine were administered intravenously.No suggestion was made in these publications that cyclosporine could beorally administered to substantially increase the bioavailability oforally administered anti-cancer drugs and other pharmaceutical agentswhich are themselves poorly absorbed from the gut without producinghighly toxic side effects. None of the published studies provided anyregimen for implementing the effective oral administration to humans ofpoorly bioavailable drugs such as paclitaxel, e.g., indicating therespective dosage ranges and timing of administration for specifictarget drugs and bioavailability-enhancing agents are best suited forpromoting oral absorption of each target drug or class of drugs.

In published PCT application WO 95/20980 (published Aug. 10, 1995) Benetet al. disclose a purported method for increasing the bioavilability oforally administered hydrophobic pharmaceutical compounds. This methodcomprises orally administering such compounds to the patientconcurrently with a bioenhancer comprising an inhibitor of a cytochromeP450 3A enzyme or an inhibitor of P-glycoprotein-mediated membranetransport. Benet et al., however, provide virtually no means foridentifying which bioavailability enhancing agents will improve theavailability of specific “target” pharmaceutical compounds, nor do theyindicate specific dosage amounts, schedules or regimens foradministration of the enhancing or target agents. In fact, although theBenet et al. application lists dozens of potential enhancers (P450 3Ainhibitors) and target drugs (P450 3A substrates), the only combinationof enhancer and target agent supported by any experimental evidence inthe application is ketoconazole as the enhancer and cyclosporin A as thetarget drug.

When describing the general characteristics of compounds which can beused as bioenhancers by reduction of P-glycoprotein transport activity,Benet et al. indicate that these are hydrophobic compounds whichgenerally, but not necessarily, comprise two co-planar aromatic rings, apositively charged nitrogen group or a carbonyl group—a class thatincludes an enormous number of compounds, most of which would notprovide the desired absorption enhancing activity in the case ofspecific target agents. Moreover, the classes of target agents disclosedby Benet et al. include the great majority of pharmaceutical agentslisted in the Physicians' Desk Reference. These inclusion criteria areof no value to medical practitioners seeking safe, practical andeffective methods of orally administering specific pharmaceuticalagents.

In general, Benet et al. provides no teaching that could be followed bypersons skilled in the medical and pharmaceutical arts to identifysuitable bioenhancer/target drug combinations or to design specifictreatment regimens and schedules which would render the target agentstherapeutically effective upon oral administration to human patients.Benet et al. also provides no direction whatsoever regarding howpaclitaxel and other taxanes might be administered orally to humans withtherapeutic efficacy and acceptable toxicity.

In published PCT application WO 97/15269, which corresponds to U.S.patent application Ser. No. 08/733,142 (the grandparent of the presentapplication) and which is commonly owned with this application, it isdisclosed that various therapeutically effective pharmaceutical “targetagents” which exhibit poor oral bioavailability can be madebioavailable, providing therapeutic blood levels of the active agent, byoral co-administration of certain bioavailability enhancing agents.Preferred examples of such target agents disclosed in WO 97/15269include the cyclosporins, e.g., cyclosporins A, D and G. Preferredexamples of target agents include the taxane class of antineoplasticagents, particularly paclitaxel. Therapeutic regimens and dosage amountsfor co-administration for target agents and enhancing agents are alsodisclosed. All of the disclosures of published application WO 97/15269are incorporated herein by reference.

Neither commonly owned application WO 97/15269 nor any prior artdisclosure, however, describes classes of oral formulations orcompositions containing the active target agent, e.g., paclitaxel, whichare particularly adapted for co-administration with an oralbioavailability enhancing agent to yield therapeutic blood levels oftarget agents heretofore considered unsuitable for oral administration.

SUMMARY OF THE INVENTION

The present invention relates to oral pharmaceutical compositionscontaining taxane antitumor agents, for example paclitaxel or docetaxel,which, when administered to a mammalian patient, preferably withco-administration of an oral bioavailability enhancing agent, enablesufficient absorption of the taxane agent from the gastrointestinaltract into the bloodstream to provide therapeutically significant bloodlevels of the active drug.

The compositions of the invention comprise a vehicle including a carrierin which the taxane agent is dissolved or dispersed. The vehicle mayalso include a viscosity-reducing co-solubilizer which renders thevehicle more flowable at body temperature or at least reduces themelting point of the vehicle below body temperature, and may alsoprovide increased taxane solubility.

The carrier used in the novel compositions is preferably a non-ionicsurface active agent (surfactant) or emusifier having ahydrophilic-lipophilic balance (HLB) value at least about 10. Theviscosity-reducing co-solubilizer is selected from, e.g., organicsolvents suitable for oral administration, vegetable oils, hydrogenatedor polyoxyethylated castor oil, citrate esters and saturatedpolyglycolized glycerides. Certain saturated polyglycolized glyceridesmay also serve as carriers in the compositions of the invention.

The novel pharmaceutical compositions contain about 2-500 mg/ml or mg/gof taxane, and preferably about 2-50 mg/ml or mg/g of taxane. Thetherapeutically inactive vehicle comprises at least 30% by weight ofcarrier and about 0-70% of co-solubilizer, and may also containconventional pharmaceutical additives and excipients such as flavoringand coloring agents and the like.

Another aspect of the invention pertains to methods of treatment ofmammalian patients suffering from taxane-responsive disease conditionsby the administration to such patients of oral pharmaceuticalcompositions in accordance with the invention, preferably withco-administration of an oral bioavailability enhancing agent.

DETAILED DESCRIPTION OF THE INVENTION

The oral pharmaceutical compositions of the invention contain at leasttwo components: an active agent comprising a taxane, preferably theantitumor agent paclitaxel or docetaxel, and a therapeutically inactivevehicle comprising a pharmaceutically acceptable carrier for saidtaxane.

In order to produce compositions for oral administration that are liquidor at least flowable form at body temperature (about 37° C.), asgenerally required for oral bioavailability, it is required in someinstances to add an additional component to the vehicle: aviscosity-reducing co-solubilizer which decreases the viscosity andincreases the flowability of the vehicle at body temperature, and alsomay increase the amount of the active agent that can be dissolved ordispersed in the vehicle in comparison with the use of a carrier alone.

The novel compositions may comprise more than one taxane as activeingredient and more than one carrier and/or co-solubilizer as inactivevehicle components. The vehicle comprises at least 30% by weight ofcarrier, preferably 30-90% by weight. Preferred carriers for use in theinvention are non-ionic surfactants or emulsifiers having HLB values atleast about 10. It has been found that such non-ionic surfactants oremulsifiers are not only compatible carriers for the lipophilic taxanes(which are poorly soluble in water) but also promote absorption of theactive ingredient from the gastrointestinal tract into the bloodstream.

Preferred carriers for use in the invention include, for example,Vitamin E TPGS (d- -tocopheryl polyethylene glycol 1000 succinate,Eastman Chemical Co., Kingsport Tenn.); saturated polyglycolyzedglycerides such as GELUCIRE™ and LABRASOL™ products (Gattefossé Corp.,Westwood, N.J.) which include glycerides of C₈-C₁₈ fatty acids;CREMOPHOR™ EL or RH40 modified castor oils (BASF, Mt. Olive, N.J.);MYRJ™ polyoxyethylated stearate esters (ICI Americas, Charlotte, N.C.);TWEEN™ (ICI Americas) and CRILLET™ (Croda Inc., Parsippany, N.J.)polyoxyethylated sorbitan esters; BRIJ™ polyoxyethylated fatty ethers(ICI Americas); CROVOL™ modified (polyethylene glycol) almond and cornoil glycerides (Croda Inc.); EMSORB™ sorbitan diisostearate esters(Henkel Corp., Ambler, Pa.); SOLUTOL™ polyoxyethylated hydroxystearates(BASF); and -cyclodextrin. Only those members of these surfactantfamilies which have HLB values of about 10 or greater may be used ascarriers in the subject compositions.

Preferred viscosity-reducing co-solubilizers include, e.g., PHARMASOLVE™(N-methyl-2-pyrrolidone, International Specialty Products, Wayne, N.J.);MIGLYOL™ glycerol or propylene glycol esters of caprylic and capricacids (Hüls AG, Marl, Germany); polyoxyethylated hydroxystearates (e.g.,SOLUTOL™ HS 15); TWEEN™ polyoxyethylated sorbitan esters; SOFTIGEN™polyethylene glycol esters of caprylic and capric acids (Hüls AG);modified castor oils (such as CREMOPHOR™ EL or RH 40); vegetable oilssuch as olive oil, polyoxyethylated fatty ethers or modified castoroils; certain saturated polyglycolyzed glycerides (such as a LABRASOL™)citrate esters such as tributyl citrate, triethyl citrate and acetyltriethyl citrate; propylene glycol, alone or in combination withPHARMASOLVE™; ethanol; water; and lower molecular weight polyethyleneglycols such as PEG 200 and 400.

The vehicle contains about 0-70% by weight of the co-solubilizer, andpreferably about 10-50% by weight. It will be noted that several of thematerials identified as carriers have also been found to be effectiveco-solubilizers, either alone or in combination with otherviscosity-reducing agents, for certain other carriers. In general, anysolvent in which paclitaxel or other taxanes are at least moderatelysoluble at body temperature or with gentle heating can be used as aco-solubilizer in the vehicle of the novel compositions. Preferredco-solubilizers are those in which at least 25 mg/ml of paclitaxel orother taxane can be solubilized at about 20-25° C.

The concentration of the active taxane ingredient or ingredients in thecomposition may vary based on the solubility of the active agent in thecarrier(s) or carrier(s)/co-solubilizer(s) system and on the desiredtotal dose of taxane to be administered orally to the patient. Theconcentration of taxane may range from about 2 to about 500 mg/ml ormg/g of vehicle, and preferably from about 2 to about 50 mg/ml or mg/g.

The compositions of the invention may be prepared by any conventionalmethod known to individuals of skill in the pharmaceutical arts forpreparing liquid or other fluid oral formulations containing surfactantcarriers and lipophilic active ingredients. Since the majority of thepreferred carriers are very viscous at room temperature, and in somecases retain a relatively high viscosity even upon the addition of aminor proportion of co-solubilizer, it is generally preferred inpreparing the novel compositions to mix the carriers and co-solubilizersto be used, add the taxane active ingredient, and heat the resultingmixture while stirring, for example to about 40° C. This method enablesthe preparation of clear solutions. Certain co-solubilizers, however,particularly PHARMASOLVE™, lower the carrier viscosity and enhancetaxane solubility to such a degree that the composition can be preparedby stirring at room temperature with no heating.

It is desirable that the viscosity of the finished composition not behigher than 40,000 cps at body temperature (approximately 37° C.).

The oral compositions of the invention may be in the form of truesolutions, emulsions or even suspensions, but solutions of the activetaxane ingredient in the carrier or carrier/co-solubilizer system arepreferred.

The present invention also comprehends methods of treating humanpatients afflicted with cancers, tumors, Kaposi's sarcoma, malignancies,uncontrolled tissue or cellular proliferation secondary to tissueinjury, and any other disease conditions responsive to taxanes such aspaclitaxel and docetaxel, and/or prodrugs and derivatives of theforegoing, with the novel orally administered pharmaceuticalcompositions. Among the types of carcinoma which may be treatedparticularly effectively with oral paclitaxel, docetaxel, other taxanes,and their prodrugs and derivatives, are hepatocellular carcinoma andliver metastases, cancers of the gastrointestinal tract, pancreas,prostate and lung, and Kaposi's sarcoma. Examples of non-cancerousdisease conditions which may be effectively treated with these activeagents administered orally in accordance with the present invention areuncontrolled tissue or cellular proliferation secondary to tissueinjury, polycystic kidney disease, inflammatory diseases (e.g.,arthritis) and malaria, including chloroquine- andpyrimethamine-resistant malaria parasites (Pouvelle et al., J. Clin.Invest., 44: 413-417, 1994).

Although some of the oral pharmaceutical compositions of the inventionmay provide therapeutic blood levels of the taxane active ingredientwhen administered alone, the preferred method of the invention fortreating mammalian patients (particularly human patients) suffering fromtaxane-responsive disease conditions is to administer the oralcompositions containing the taxane target agent concomitantly with theadministration of at least one dose of an oral bioavailability enhancingagent.

The preferred embodiment of the method of the invention for oraladministration to humans of paclitaxel, its derivatives, analogs andprodrugs, and other taxanes comprises the oral administration of an oralabsorption or bioavailability enhancing agent to a human patientsimultaneously with, or prior to, or both simultaneously with and priorto the oral administration to increase the quantity of absorption of theintact target agent into the bloodstream. The orally administeredenhancing agents which may be used in practicing the preferredembodiment of the invention include, but are not limited to, thefollowing:

Cyclosporins, including cyclosporins A through Z but particularlycyclosporin A (cyclosporine), cyclosporin F, cyclosporin D, dihydrocyclosporin A, dihydro cyclosporin C, acetyl cyclosporin A, PSC-833,SDZ-NIM 811¹ (both from Sandoz Pharmaceutical Corp). The structures ofcyclosporins A-Z are described in Table 1 below.SDZ-NIM 811 is (Me-Ile-4)-cyclosporin, an antiviral,non-immunosuppressive cyclosporin.TABLE 1 Cyclosporins A-Z Cyclosporin Aminoacids Cy- 1 2 3 4 5 6 7 8 9 1011 CyA Mebmt Abu Sar MeLeu Val MeLeu Ala D-Ala MeLeu MeLeu MeVal CyBMebmt Ala Sar MeLeu Val MeLeu Ala D-Ala MeLeu MeLeu MeVal CyC Mebmt ThrSar MeLeu Val MeLeu Ala D-Ala MeLeu MeLeu MeVal CyD Mebmt Val Sar MeLeuVal MeLeu Ala D-Ala MeLeu MeLeu MeVal CyE Mebmt Abu Sar MeLeu Val MeLeuAla D-Ala MeLeu MeLeu Val CyF Desoxy- Abu Sar MeLeu Val MeLeu Ala D-AlaMeLeu MeLeu MeVal Mebmt CyG Mebmt Nva Sar MeLeu Val MeLeu Ala D-AlaMeLeu MeLeu MeVal CyH Mebmt Abu Sar MeLeu Val MeLeu Ala D-Ala MeLeuMeLeu D-Mev CyI Mebmt Val Sar MeLeu Val MeLeu Ala D-Ala MeLeu Leu MeValCyK Desoxy- Val Sar MeLeu Val MeLeu Ala D-Ala MeLeu MeLeu MeVal MebmtCyL Bmt Abu Sar MeLeu Val MeLeu Ala D-Ala MeLeu MeLeu MeVal CyM MebmtNva Sar MeLeu Val MeLeu Ala D-Ala MeLeu MeLeu MeVal CyN Mebmt Nva SarMeLeu Val MeLeu Ala D-Ala MeLeu Leu MeVal CyO MeLeu Nva Sar MeLeu ValMeLeu Ala D-Ala MeLeu MeLeu MeVal CyP Bmt Thr Sar MeLeu Val MeLeu AlaD-Ala MeLeu MeLeu MeVal CyQ Mebmt Abu Sar Val Val MeLeu Ala D-Ala MeLeuMeLeu MeVal CyR Mebmt Abu Sar MeLeu Val Leu Ala D-Ala MeLeu Leu MeValCyS Mebmt Thr Sar Val Val MeLeu Ala D-Ala MeLeu MeLeu MeVal CyT MebmtAbu Sar MeLeu Val MeLeu Ala D-Ala MeLeu Leu MeVal CyU Mebmt Abu SarMeLeu Val Leu Ala D-Ala MeLeu MeLeu MeVal CyV Mebmt Abu Sar MeLeu ValMeLeu Ala D-Ala MeLeu MeLeu MeVal CyW Mebmt Thr Sar MeLeu Val MeLeu AlaD-Ala MeLeu MeLeu Val CyX Mebmt Nva Sar MeLeu Val MeLeu Ala D-Ala LeuMeLeu MeVal CyY Mebmt Nva Sar MeLeu Val Leu Ala D-Ala MeLeu MeLeu MeValCyZ MeAmino Abu Sar MeLeu Val MeLeu Ala D-Ala MeLeu MeLeu MeVal octylacid

Cyclosporins are a group of nonpolar cyclic oligopeptides (some of whichhave immunosuppressant activity) produced by the genus, Tolypocladium,including, e.g., Tolypocladium inflatum Gams (formerly designated asTrichoderma Polysporum), Tolypocladium terricola and other fungiimperfecti. The major component, cyclosporin A (cyclosporine or CsA),has been identified along with several other lesser metabolites, forexample, cyclosporins B through Z, some of which exhibit substantiallyless immunosuppressive activity than cyclosporin A. A number ofsynthetic and semi-synthetic analogs have also been prepared. Seegenerally Jergorov et al., Phytochemistry, 38: 403-407 (1995). Thepresent invention comprehends natural, semi-synthetic and syntheticanalogs of cyclosporins.

Cyclosporins are neutral, lipophilic, cyclic undecapeptides withmolecular weights of about 1200. They are used intravenously or orallyas immunosuppressants, primarily for organ transplantation and certainother conditions. Cyclosporins, particularly cyclosporine (cyclosporinA), are known inhibitors of the P-glycoprotein efflux pump and othertransporter pumps as well as of certain P450 degradative enzymes, but todate no effective regimens for applying this property clinically havebeen developed to the point of clinical and commercial feasibility orregulatory approval.

The dosage range of the enhancing agent to be co-administered with thetarget agent in accordance with the invention is about 0.1 to about 20mg/kg of patient body weight. “Co-administration” of the enhancing agentcomprehends administration substantially simultaneously with the targetagent (either less than 0.5 hr. before, less than 0.5 hr. after ortogether), from about 0.5 to about 72 hr. before the administration ofthe target agent, or both, i.e., with one or more doses of the same ordifferent enhancing agents given at least 0.5 hr. before and one dosegiven substantially simultaneously with (either together with orimmediately before of after) the target agent. Additionally,“co-administration” comprehends administering more than one dose oftarget agent within 72 hr. after a dose of enhancing agent, in otherwords, the enhancing agent(s) need not be administered again before orwith every administration of target agent, but may be administeredintermittently during the course of treatment.

The dosage range of orally administered taxane target agents will varyfrom compound to compound based on its therapeutic index, therequirements of the condition being treated, the status of the subjectand so forth. The method of the invention makes it possible toadminister paclitaxel and other taxanes orally ranging from about 20mg/m² to about 1000 mg/m² (based on patient body surface area) or about0.5-30 mg/kg (based on patient body weight) as single or divided (2-3)daily doses, and maintain the plasma levels of paclitaxel in humans inthe range of 50-500 ng/ml for extended periods of time (e.g., 8-12hours) after each oral dose. These levels are at least comparable tothose achieved with 96-hour IV infusion paclitaxel therapy (which causesthe patient great inconvenience, discomfort, loss of quality time,infection potential, etc.). Moreover, such plasma levels of paclitaxelare more than sufficient to provide the desired pharmacologicalactivities of the target drug, e.g., inhibition of tubulin disassembly(which occurs at levels of about 0.1 □M, or about 85 ng/ml) andinhibition of protein isoprenylation (which occurs at levels of about0.03 □M, or about 25 ng/ml) which are directly related to its antitumoreffects by inhibiting oncogene functions and other signal-transducingproteins that play a pivotal role in cell growth regulation.

Two or more different enhancing agents and/or two or more differenttaxane target agents may be administered together, alternately orintermittently in all of the various aspects of the method of theinvention.

As indicated above, oral paclitaxel administered alone (e.g., in a soliddosage form or even in a liquid vehicle not containing an oralabsorption promoting carrier) exhibits near zero bioavailability. To beconsidered an orally bioavailable pharmaceutical composition containingpaclitaxel or other taxanes for purposes of the present invention, thecomposition must meet the following criterion: when the composition isadministered orally to a mammalian subject (e.g., a laboratory rat or ahuman patient), i.e., is ingested by the subject, one hour afteradministration of an effective oral dose of an oral bioavailabilityenhancing agent, the amount of the active ingredient absorbed into thebloodstream is at least 15% of the amount absorbed when the same dose ofpaclitaxel is administered to the subject intravenously in a standardintravenous vehicle, for example a CREMOPHOR™ EL/ethanol vehicle. Therelative percentage of absorption is determined by comparing therespective AUC (area under the curve) values of the taxane blood levelvs. time curve generated upon oral administration and the correspondingcurve generated upon intravenous administration.

The preferred bioavailability enhancing agent for use in making theexperimental determination of whether a particular oral compositionmeets the 15% of IV absorption criterion is cyclsoporin A, for example asingle oral dose of 5 mg/kg of CsA.

The novel pharmaceutical compositions may be administered in any knownpharmaceutical dosage form. For example, the compositions may beencapsulated in a soft or hard gelatin capsule or may be administered inthe form of a liquid preparation. Each dosage form may include, apartfrom the essential components of the composition (at least one carrierand one taxane active ingredient, and in some instances at least oneco-solubilizer), conventional pharmaceutical excipients, diluents,sweeteners, flavoring agents, coloring agents and any other inertingredients regularly included in dosage forms intended for oraladministration (see, e.g., Remington's Pharmaceutical Sciences, 17thEd., 1985).

Precise amounts of each of the target drugs included in the oral dosageforms will vary depending on the age, weight, disease and condition ofthe patient. For example, paclitaxel or other taxane dosage forms maycontain sufficient quantities of the target agent to provide a dailydosage of about 20-1000 mg/m² (based on mammalian subject or patientbody surface area) or about 0.5-30 mg/kg (based on mammalian subject orpatient body weight) as single or divided (2-3) daily doses. Preferreddosage amounts are about 50-200 mg/m² or about 2-6 mg/kg.

Dosing schedules for the treatment method of the present invention, forexample, the treatment of paclitaxel-responsive diseases with oralpaclitaxel dosage forms co-administered with enhancing agents, canlikewise be adjusted to account for the patient's characteristics anddisease status. Preferred dosing schedules for administration of oralpaclitaxel are (a) the daily administration to a patient in need thereofof 1-3 equally divided doses providing about 20-1000 mg/m² (based onbody surface area), and preferably about 50-200 mg/m², with said dailyadministration being continued for 1-4 consecutive days each 2-3 weeks,or (b) administration for about one day each week. The former scheduleis comparable to use of a 96-hour paclitaxel infusion every 2-3 weeks,which is considered by some a preferred IV treatment regimen.

Oral administration of taxanes in accordance with the invention mayactually decrease toxic side effects in many cases as compared withcurrently utilized IV therapy. Rather than producing a sudden and rapidhigh concentration in blood levels as is usually the case with an IVinfusion, absorption of the active agent through the gut wall (promotedby the enhancing agents), provides a more gradual appearance in theblood levels and a stable, steady-state maintenance of those levels ator close to the ideal range for a long period of time.

In a further embodiment of the present invention, the oral compositionsof the invention may be administered in a two-part medicament system.Thus, for example, there may be certain carriers coming within the scopeof the invention which are desirable for use in vehicles for certaintaxane agents because of their ability to solubilize the taxane andpromote its oral absorption, but the carrier may be chemically orphysically incompatible with desired adjunctive ingredients such asflavoring or coloring agents. In such cases, the active ingredient canbe administered to the patient as the first part of the medicament in arelatively small volume of any suitable liquid solubilizing vehicle(such as water, CREMOPHOR™ or ethanol), which may be sweetened, flavoredor colored as desired to mask the unpleasant taste of the vehicle andrender it more palatable. The administration of the active ingredientcan be followed by administration of the second part of the medicament:a larger volume of fluid, for example 1 to 8 fluid ounces (30-240 ml),containing at least one carrier or a carrier/co-solubilizer system inaccordance with the invention. It has been discovered thatadministration of the second, “chaser” formulation a short time afterthe taxane active ingredient can retard precipitation of the taxanewhich might otherwise occur upon entry into the gastric fluid andpromote oral absorption to a degree comparable to that observed when thetaxane is intermixed with the carrier and administered simultaneously.Illustrative examples of “chaser” formulations which may be used in atwo-part oral taxane medicament include:

-   -   a) 2-20% (by weight) Vitamin E TPGS+water q.s.;    -   b) 2-25% Vitamin E TPGS+2-25% PHARMASOLVE™+water q.s.;    -   c) 2-20% Vitamin E TPGS+2-25% propylene glycol+water q.s.

Pursuant to yet another aspect of the invention, the oral compositionsof the invention can contain not only one or more taxane activeingredients but also one or more bioavailability enhancing agents in acombination dosage form. For example, such combination dosage form maycontain from about 0.1 to about 20 mg/kg (based on average patient bodyweight) of one or more of cyclosporins A, D, C, F and G, dihydro CsA,dihydro CsC and acetyl CsA together with about 20 to about 1000 mg/m²(based on average patient body surface area), and preferably about50-200 mg/m², of paclitaxel, docetaxel, other taxanes or paclitaxel ordocetaxel derivatives.

The compositions and methods of the present invention provide manyadvantages in comparison with prior art intravenous compositionscontaining paclitaxel and other taxanes and prior art intravenousadministration regimens. Apart from the issues of decreased toxicity,patient convenience and comfort, ease of administration and loweredexpense, discussed previously, the invention makes it possible toadminister powerful taxane antitumor agents to patients with greatlyreduced likelihood of allergic hypersensitivity reactions which arecommon with IV administration. Thus, the need for pre-medicationregimens of H-1 and H-2 blockers plus steroids can be eliminated.

The present invention also makes it possible to give taxanes, e.g.,paclitaxel, in comparatively infrequent daily doses (e.g., abouttwice/day) and according to schedules that would otherwise not bepossible or practical with the intravenous route. The use of thebioavailability enhancer (e.g., cyclosporin A) promotes oral absorptionof paclitaxel for the first dose and if a second paclitaxel dose is tobe given later in the day, the use of additional cyclosporin A may noteven be needed. Thus, paclitaxel could be given intermittently as singledose on a fixed schedule (weekly, biweekly, etc.) or chronically, over aperiod of consecutive days (e.g., 4 days) every 2-4 weeks with the goalof keeping the levels within a safe and effective “window”.

The following examples illustrate various aspects of the invention.These examples are not intended, however, to limit the invention in anyway or to set forth specific active ingredients, carriers,co-solubilizers, enhancing agents, dosage ranges, testing procedures orother parameters which must be used exclusively to practice theinvention.

EXAMPLE 1 Animal Screening Model

Groups of three male rats each were fasted for 16-18 hours prior todosing with ³H-radiolabeled paclitaxel. Each group of animals receivedone oral dose of cyclosporin A (5 mg/kg) prior to dosing withexperimental oral paclitaxel formulation. One hour subsequent tocyclosporin dosing, each group received approximately 9 mg/kg ofpaclitaxel orally in the form of a composition according to theinvention. Each group received a different oral formulation.

Blood samples were collected from each animal at 0.5, 1, 2, 3, 4, 6, 8,12 and 24 hours post-dose of paclitaxel. The blood samples werecombusted and assayed for total radioactivity.

The total blood radioactivity levels (corresponding to concentration inthe blood of ³H-paclitaxel) were plotted on a graph vs. time post-dose.Data for each group of rats were compiled in the form of mean AUC,C_(max) and T_(max).

The percentage of absorption of ³H-paclitaxel for each group of animalswas calculated by comparing the mean AUC value for the group to thecorresponding mean AUC of a reference group of rats administered³H-paclitaxel (9 mg/kg) intravenously in the form of PAXENE™ (BakerNorton Pharmaceuticals, Miami Fla.) which includes CREMOPHOR™ EL,ethanol and citric acid.

Table 2 lists all carriers and carrier/co-solubilizer combinations whichwere formulated into oral compositions containing paclitaxel inaccordance with the invention, were tested in rats in accordance withthe foregoing procedure and were found to yield percentage absorptionvalues in the experimental animals of 15% or greater in comparison withIV paclitaxel. TABLE 2 Carriers and carrier/co-solubilizer combinationswhich achieved greater than 15% paclitaxel absorption CarriersCo-solubilizers TPGS Pharmasolve Propylene Mygliols Softigen PEG 200 &Propylene PEG 200 & glycol 400 glycol/ 400/ Pharmasolve PharmasolveGelucire 44/14 Pharmasolve Mygliols Olive oil/ Olive Olive oil/Cremophor EL Cremophor Brij 97 oil/ TPGS RH 40 Cremophor RH 40 Gelucire44/14 Labrasol TPGS/ Tween 80 PEG 400 Solutol HS 15 Gelucire 50/13 Tween80 PEG 400 Cremophor EL Cremophor EL Pharmasolve Citrate Ethanol/waterEthanol esters Cremophor RH 40 Ethanol/water Myrj 49 Pharmasolve Myrj 52Pharmasolve Propylene glycol Myrj 53 Pharmasolve Tween 40* Tween 60*Tween 80* Ethanol Citrate Olive oil PEG 400 Water esters Crillet 6*Emsorb 2726 Pharmasolve Solutol HS 15* Brij 76 Pharmasolve Brij 78Pharmasolve Brij 98 Pharmasolve Crovol A-40* Crovol M-40* .-CyclodextrinWater*Have been demonstrated to work as both solubilizer and carrierNote:All carriers listed above can solubilize paclitaxel greater than 25mg/ml at 37□ C.

EXAMPLE 2 Polyoxyethylated (POE) Sorbitan Fatty Acid Esters as Carriers

Table 3 lists vehicle formulations including certain POE sorbitan fattyacid esters as carriers for oral paclitaxel, alone or in combinationwith a co-solubilizer. In formulations where more than one component ispresent in the vehicle, the respective weight ratios of the componentsis given. Each of these formulations was tested in the animal modeldescribed in Example 1 and found to yield a percentage absorption ofpaclitaxel upon oral administration greater (in some cases far greater)than 15% of a roughly comparable dose of paclitaxel administeredintravenously. The table sets forth the total dose of paclitaxelincorporated into each vehicle as actually administered to theexperimental animals, the concentration of paclitaxel in thecomposition, the HLB value of the carrier, the mean AUC value for thegroup of rats receiving the formulation and the percentage of paclitaxelabsorption in comparison with rats receiving IV administration. TABLE 3Absorption Results of Polyoxyethylated (POE) Sorbitan Fatty Acid EstersSurfactants as Carriers AUC Dose Conc. □g · [mg/ [mg/ eq × hr/ %FORMULATIONS kg] ml] HLB ml ABS* POE 20 sorbitan 10.2 18 16.7 17.2 54.6monolaurate (Tween 20) POE 20 sorbitan 10.2 18 15.6 17.6 55.9monopalmitate (Tween 40) POE 20 sorbitan 8.9 25 14.9 17.1 62.3monostearate (Tween 60) POE 20 sorbitan 9.4 25 10.5 6.15 21.1tristearate (Tween 65) POE 20 sorbitan 9.0 18 15.0 11.4 40.9 monooleate(Tween 80) POE 20 sorbitan 9.3 20 14.9 13.6 47.5 monoisostearate(Crillet 6) POE 40 sorbitan 10.2 25  15.0* 7.76 24.6diisostearate/Pharmasolve (3:1) [Emsorb 2726]*Percent absorption versus paclitaxel IV AUC (same for Tables 4-11)

EXAMPLE 3 POE Alkyl Ethers as Carriers

Table 4 pertains to vehicle formulations containing POE alkyl ethers ascarriers. The data set forth correspond to the data described in thepreceding example with respect to Table 3. TABLE 4 Absorption Results ofPolyoxyethylated (POE) Alkyl Ethers Surfactants as Carriers AUC DoseConc. □g · eq × % FORMULATIONS [mg/kg] [mg/ml] HLB hr/ml ABS POE 10stearyl 10.2 18 12.4* 9.54 30.3 ether/Pharmasolve (3:1) [Brij 76] POE 20stearyl 9.5 18 15.3* 11.4 38.7 ether/Pharmasolve (3:1) [Brij 78] POE 20oleyl 9.6 25 15.3* 5.89 20.9 ether/Pharmasolve (3:1) [Brij 98]*Not an actual HLB value of mixture. Numbers represent HLB values ofpure surfactants.

EXAMPLE 4 POE Stearates as Carriers

Table 5 pertains to vehicle formulations containing POE stearates ascarriers. The data set forth correspond to the data described in Example2 with respect to Table 3. TABLE 5 Absorption Results ofPolyoxyethylated (POE) Stearates as Carriers AUC Dose Conc. □g · eq × %FORMULATIONS [mg/kg] [mg/ml] HLB hr/ml ABS POE 20 stearate 9.2 25 15.0*10.3 36.4 ester/Pharmasolve (3:1) [Myrj 49] POE 40 stearate 9.4 18 16.9*16.2 57.3 ester/Pharmasolve (3:1) [Myrj 52] POE 50 stearate 10.0 2517.9* 7.01 22.3 ester/Pharmasolve (3:1) [Myrj 53]*Not an actual HLB value of mixture. Numbers represent HLB values ofpure surfactants.

EXAMPLE 5 Ethoxylated Modified Triglycerides as Carriers

Table 6 pertains to vehicle formulations containing ethoxylated-modifiedtriglycerides as carriers. The data set forth correspond to the datadescribed in Example 2 with respect to Table 3. TABLE 6 AbsorptionResults of Ethoxylated Modified Triglycerides as Carriers AUC Dose Conc.□g · eq × % FORMULATIONS [mg/kg] [mg/ml] HLB hr/ml ABS PEG-20 Almond 9.520 10 8.06 27.6 Glycerides (Crovol A-40) PEG-20 Corn 9.6 20 10 7.46 25.3Glycerides (Crovol M-40)

EXAMPLE 6 POE 660 Hydroxystearates as Carriers

Table 7 pertains to vehicle formulations containing POE 660hydroxystearates as carriers. The data set forth correspond to the datadescribed in Example 2 with respect to Table 3. TABLE 7 AbsorptionResults of Polyoxyethylated (POE) 660 Hydroxystearate as Carrier AUCDose Conc. □g · eq × % FORMULATIONS [mg/kg] [mg/ml] HLB hr/ml ABS POE660 hydroxystearate 9.1 25 ˜14 10.8 38.4 (Solutol HS 15) Gelucire44/14 + Solutol 9.3 25 ˜14 6.54 22.8 HS + TPGS (2:1:1)

EXAMPLE 7 Saturated Polyglycolized Glycerides as Carriers

Table 8 pertains to vehicle formulations containing saturatedpolyglycolyzed glycerides as carriers. The data set forth correspond tothe data described in Example 2 with respect to Table 3. TABLE 8Absorption Results of Saturated Polyglycolized Glycerides as CarriersAUC Dose Conc. □g · eq × FORMULATIONS [mg/kg] [mg/ml] hr/ml % ABSGelucire 44/14 + PEG 400 10.3 25 11.9 37.4 (6:1) Gelucire 44/14 +Labrasol 9.3 25 12.1 42.1 (6:1) Gelucire 44/14 + Mygliol 8.7 25 4.7517.6 810 (6:1) Gelucire 44/14 + Mygliol 10.3 25 8.45 26.6 818 (6:1)Gelucire 44/14 + Mygliol 9.5 25 6.48 22.0 840 (6:1) Gelucire 44/14 +Cremophore 9.5 25 10.7 36.6 RH 40 (6:1) Gelucire 44/14 + Cremophor 9.825 11.5 38.1 EL (6:1) Gelucire 44/14 + Solutol 9.3 25 6.54 22.8 HS +TPGS (2:1:1) Gelucire 44/14 + Olive 9.6 20 11.9 39.9 Oil + Tween 80(2:1:1) Gelucire 44/14 + Olive 9.6 20 9.83 33.2 Oil + TPGS (2:1:1)Gelucire 44/14 + Olive 9.6 20 9.07 30.6 Oil + POE 10 Oleyl (2:1:1)Gelucire 44/14 + Olive 9.1 20 7.73 27.5 Oil + Cremophor RH 40 (2:1:1)Gelucire 44/14 + Tween 9.7 25 10.05 33.5 80 (6:1) Gelucire 50/13 + Tween9.4 25 8.21 28.4 80 (5:2) Gelucire 50/13 + PEG 400 9.3 25 6.46 22.5(6:1) Gelucire 50/13 + Cremophor 9.1 25 8.11 28.9 EL (6:1)Labrasol: Saturated polyglycolyzed C8-C10 glycerides (HLB = 14)Mygliols: Neutral oils (saturated coconut and palmkernel fatty acids)mainly C8-C10 fatty acidsCremophor EL: Polyoxyl 35 castor oil (HLB 12-14)Cremophor RH 40: Polyoxyl 40 Hydrogenated castor oil (HLB 14-16)

EXAMPLE 8 Vitamin E TPGS Systems as Carriers

Table 9 pertains to vehicle formulations containing Vitamin E TPGSsystems as carriers. The data set forth correspond to the data describedin Example 2 with respect to Table 3. TABLE 9 Absorption Results of TPGSSystems as Carriers AUC Dose Conc. □g · eq × FORMULATIONS [mg/kg][mg/ml] hr/ml % ABS* TPGS + Pharmasolve 8.2 25 8.93 35.2 (1.5:1) TPGS +Pharmasolve 9.5 25 8.72 29.8 (1:1) TPGS + Pharmasolve 9.1 25 8.83 31.4(2:1) TPGS + Propylene 8.5 20 9.65 36.9 glycol (1:1) TPGS +Pharmasolve + 9.0 25 8.31 29.8 PEG 200 (2:1:1) TPGS + Pharmasolve + 8.225 6.62 26.3 PEG 400 (2:1:1) TPGS + Pharmasolve + 8.9 25 8.07 29.3 PG(2:1:1) TPGS + Mygliol 810 9.1 25 5.65 20.0 (1:1) TPGS + Softigen 76710.2 25 8.66 27.5 (1:1) TPGS + PEG 200 (1:1) 8.3 25 7.75 30.4 TPGS + PEG400 (1:1) 9.6 25 7.32 24.6Softigen 767: PEG-6-Caprylic/Capric Glycerides

EXAMPLE 9 POE and Hydrogenated Castor Oil Derivatives as Carriers

Table 10 pertains to vehicle formulations containing POE andhydrogenated castor oil derivatives as carriers. The data set forthcorrespond to the data described in Example 2 with respect to Table 3.TABLE 10 Absorption Results of Polyoxyethylated Castor Oil (Cremophor)Derivatives Systems as Carriers Dose Conc. AUC [mg/ [mg/ □g · eq ×FORMULATIONS kg] ml] hr/ml % ABS IV Paxene 10.0 6 11.15 37.2 CremophorEL + Ethanol + 9.2 1.3 6.07 21.5 Water (1:1:8) IV Paxene + Water (1:1)8.9 3 8.70 31.8 IV Paxene + Water (1:5) 9.1 1 10.76 38.5 Cremophor EL +Pharmasolve 8.6 20 6.74 25.3 (1:1) Cremophor EL + TBC (1:1) 9.0 20 9.3531.9 Cremophor EL + Gelucire 9.8 25 11.5 38.1 44/14 (1:6) Cremophor EL +Gelucire 9.1 25 8.11 28.9 50/13 (1:6) Cremophor RH 40 + Ethanol + 9.0 37.14 25.7 Water (1:1:2) Cremophor RH 40 + Gelucire 9.5 25 10.7 36.644/14 (1:6) Cremophor RH 40 + Gelucire 9.1 20 7.73 27.5 44/14 + OliveOil (1:2:1)

EXAMPLE 10 Polysorbate 80 Carriers

Table 11 pertains to vehicle formulations containing polysorbate 80 asat least one of the carriers. The data set forth correspond to the datadescribed in Example 2 with respect to Table 3. TABLE 11 AbsorptionResults of Polysorbate 80 (Tween 80) Systems as Carrierts Dose Conc. AUC[mg/ [mg/ □g · eq × % FORMULATIONS kg] ml] hr/ml ABS Polysorbate 80 9.018 11.4 40.9 Polysorbate 80 + Ethanol + Water 8.0 1.2 7.92 31.2 (1:1:8)Polysorbate 80 + Ethanol (3:1) 8.9 18 9.97 36.3 Polysorbate 80 + Water(3:1) 8.2 18 7.15 28.3 Polysorbate 80 + TBC (1:1) 9.5 20 9.12 31.2Polysorbate 80 + ATEC (1:1) 9.1 20 8.50 30.3 Polysorbate 80 + Olive oil(3:1) 9.0 20 13.3 43.7 Polysorbate 80 + PEG 400 (1:1) 9.7 20 9.41 31.5Polysorbate 80 + Gelucire 44/14 + 9.6 20 11.9 39.9 Olive Oil (1:2:1)Polysorbate 80 + Gelucire 44/14 9.7 25 10.05 33.5 (1:6)TBC = Tributyl citrate (citrate ester)ATEC = Acetyl triethyl citrate (citrate ester)

It has thus been shown that there are provided compositions and methodswhich achieve the various objects of the invention and which are welladapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention,and as various changes might be made in the embodiments set forth above,it is to be understood that all matters herein described are to beinterpreted as illustrative and not in a limiting sense.

What is claimed as new and desired to be protected by Letters Patent isset forth in the following claims.

1. A two-part medicament for oral administration to a mammalian subject,the first part of said medicament comprising a taxane or taxanederivative as active ingredient in a solubilizing vehicle for saidtaxane, and the second part of said medicament comprising at least 30%by weight of a carrier for the taxane, said carrier having an HLB valueat least about
 10. 2. A two-part medicament according to claim 1 whereinthe solubilizing vehicle is capable of solubilizing at least about 25mg/ml of the taxane at about 20-25° C.
 3. A two-part medicamentaccording to claim 1 wherein the solubilizing vehicle comprises water,ethanol or a polyoxyethylated or hydrogenated castor oil.
 4. A two-partmedicament according to claim 1 wherein the solubilizing vehiclecomprises sweetening, flavoring or coloring agents.
 5. A two-partmedicament according to claim 1 wherein the solubilizing vehiclecontains about 2-500 mg/ml or mg/g of the taxane.
 6. A two-partmedicament according to claim 5 wherein the solubilizing vehiclecontains about 2-50 mg/ml or mg/g of the taxane.
 7. A two-partmedicament according to claim 1 wherein the carrier includes at leastone non-ionic surfactant or emulsifier.
 8. A two-part medicamentaccording to claim 7 wherein the carrier includes at least onesurfactant or emulsifier selected from the group consisting of Vitamin ETPGS, saturated polyglycolyzed glycerides, modified castor oils,polyoxyethylated stearate esters, polyoxyethylated sorbitan esters,polyoxyethylated fatty ethers, modified almond and corn oil glyceridessorbitan diisostearate esters, polyoxyethylated hydroxystearates, andβ-cyclodextrin.
 9. A two-part medicament according to claim 1 whereinthe second part of the medicament comprises about 30-240 ml of fluid.10. A two-part medicament according to claim 1 wherein the taxane ispaclitaxel or docetaxel.
 11. A two-part medicament according to claim 10wherein the taxane is paclitaxel.
 12. A method of treating a mammaliansubject suffering from a taxane-responsive disease condition comprisingthe oral administration to the subject of a two-derivative as activeingredient in a solubilizing vehicle for said taxane and the second partof said medicament comprising at least 30% by weight of a carrier forthe taxane, said carrier having an HLB value at least about
 10. 13. Amethod according to claim 12 wherein the solubilizing vehicle is capableof solubilizing at least about 25 mg/ml of the taxane at about 20-25° C.14. A method according to claim 12 wherein the solubilizing vehiclecomprises water, ethanol or a polyoxyethylated or hydrogenated castoroil.
 15. A method according to claim 12 wherein the solubilizing vehiclecomprises sweetening, flavoring or coloring agents.
 16. A methodaccording to claim 12 wherein the solubilizing vehicle contains about2-500 mg/ml or mg/g of the taxane.
 17. A method according to claim 12wherein the solubilizing vehicle contains about 2-50 mg/ml or mg/g ofthe taxane.
 18. A method according to claim 12 wherein the carrierincludes at least one non-ionic surfactant or emulsifier.
 19. A methodaccording to claim 12 wherein the carrier includes at least onesurfactant or emulsifier selected from the group consisting of Vitamin ETPGS, saturated polyglycolyzed glycerides, modified castor oils,polyoxyethylated stearate esters, polyoxyethylated sorbitan esters,polyoxyethylated fatty ethers, modified almond and corn oil glyceridessorbitan diisostearate esters, polyoxyethylated hydroxystearates, andβ-cyclodextrin.
 20. A method according to claim 12 wherein the secondpart of the composition comprises about 30-240 ml of fluid.
 21. A methodaccording to claim 12 wherein the taxane is paclitaxel or docetaxel 22.A method according to claim 21 wherein the taxane is paclitaxel.